123456789
of 9

Solving Equations by Factoring

So...

If a * b * c = 0 , then a = 0 or b = 0 or c = 0

 

Check it out:

Solve  2a^3 - 2a = 0

Factor: 2a ( a^2 - 1 ) = 0 which gives 2a ( a - 1 ) ( a + 1 ) = 0

Blobs = 0: 2a = 0 or a - 1 = 0 or a + 1 = 0 ... Solve: divide both sides of the first equation by 2, add 1 to both sides of the second equation, subtract 1 from both sides of the third equation, giving solutions a = 0, a = 1 and a = -1

{ -1, 0, 1 }

We started with a cubed guy:  2a^3 - 2a = 0 ... the highest power is 3


and got three answers:  		{ -1, 0, 1 } is three answers: -1, 0, and 1

 

TRY IT:

Solve  5x^3 - 45x = 0